I can do you one better. An entire game filled with nothing but worst rooms.
I never played Double Dragon 2, but that at least looks possible with enough practice.
Pic related, however, is some grade-A bullshit.
It's actually fun once you git gud but the first couple play thru's are brutal.
IRON MAIDEN B2
more of a set of rooms, but time, space, and your own head flatten themselves into a benumbed dark singularity after a bit in this place
Not as hard as some of the others, but stressful and not fun.
The snake riding level is really fun. The being inside a plumbing pipe or something level can kick rocks.
Cant find an image online but at my arcade there is a Golden Axe: Revenge of Death Adder machine and one of the levels has a bunch of octopus tentacles sticking out of the ground. If you touch them even slightly it pulls you down and takes a life. Even if you cut them off they still pull you down and kill you if they are touched. You have to time your jumps perfectly to not lose like 2-3 lives in just one room. What's really brutal is the room is really close to the final fight and you need at the bare minimum 5 or 6 lives to kill death adder. Golden Axe's hit detection hasn't always been the best.
You lose the right to complain about these rooms when you have to march down three floors full of monsters to get to them, and the fact that they're only there so you can filch hilariously game-breaking gear from them.
The spirit of this thread is "UGH THOSE ROOMS" that you can't bypass, not the fact that some of the post-game content is difficult or grindy.